prefixsearch

README

prefixsearch

Golang string prefix search (for autocomplete)

go get -u github.com/ringsaturn/prefixsearch

Documentation

Overview

Package prefixsearch implements simple tree-based prefix search that i'm using for different web autocomplete services

Index

• type SearchTree
  • func New[T comparable]() *SearchTree[T]
  • func (tree *SearchTree[T]) Add(key string, value T)
  • func (tree *SearchTree[T]) AutoComplete(prefix string) []T
  • func (tree *SearchTree[T]) Search(key string) T

Examples

• SearchTree.AutoComplete
• SearchTree.AutoComplete (Unicode)
• SearchTree.Search

Types

type SearchTree

type SearchTree[T comparable] struct {
	// contains filtered or unexported fields
}

SearchTree is struct to handle search tree

func New

func New[T comparable]() *SearchTree[T]

New creates new search tree

func (*SearchTree[T]) Add

func (tree *SearchTree[T]) Add(key string, value T)

Add one leaf to tree

func (*SearchTree[T]) AutoComplete

func (tree *SearchTree[T]) AutoComplete(prefix string) []T

AutoComplete returns autocomplete suggestions for given prefix

Example

ExampleAutoComplete just creates an object and does simple test

package main

import (
	"fmt"
	"sort"

	"github.com/ringsaturn/prefixsearch"
)

func main() {
	st := prefixsearch.New[int]()
	st.Add("Hello world!", 1)
	st.Add("New impressions", 2)
	st.Add("Hello golang!", 3)
	st.Add("Привет, мир!", 4)
	st.Add("Надо же :)", 5)

	intResult := st.AutoComplete("HE")

	sort.Ints(intResult)
	fmt.Println(intResult)
}

Output:
[1 3]

Example (Unicode)

Support of unicode symbols and using struct as value

package main

import (
	"fmt"

	"github.com/ringsaturn/prefixsearch"
)

type Item struct {
	ID      int
	Name    string
	Comment string
}

func (i *Item) LessThan(j Item) bool { return i.ID < j.ID }
func (i *Item) EqualTo(j Item) bool  { return i.ID == j.ID }

func main() {

	data := []Item{
		{1, "Hello world!", "First example"},
		{2, "New impressions", "Second example"},
		{3, "Hello golang!", "Some other important info"},
		{4, "Привет, мир!", "Unicode symbols also work"},
		{5, "こんにちは世界", "Even this one may work"},
	}

	st := prefixsearch.New[Item]()
	for _, x := range data {
		st.Add(x.Name, x)
	}

	fmt.Println(st.AutoComplete("こん"))
}

Output:
[{5 こんにちは世界 Even this one may work}]

func (*SearchTree[T]) Search

func (tree *SearchTree[T]) Search(key string) T

Search searches for value of key

Example

ExampleSearch shows another possible usage of this package

package main

import (
	"fmt"

	"github.com/ringsaturn/prefixsearch"
)

func main() {
	st := prefixsearch.New[int]()
	st.Add("Hello world!", 1)
	st.Add("New impressions", 2)
	st.Add("Hello golang!", 3)
	st.Add("Привет, мир!", 4)
	st.Add("Надо же :)", 5)

	fmt.Println(st.Search("HE"))
	fmt.Println(st.Search("HELLO WORLD"))
	fmt.Println(st.Search("HELLO WORLD!"))
	fmt.Println(st.Search("HELLO WORLD!!"))

}

Output:
0
0
1
0